PRIMENA MEKIH LASERA U TERAPIJI HERPES LABIALISA pilot studija APPLICATION OF SOFT LASER IN THE TREATMENT OF HERPES LABIALIS-pilot study

Uvod: Zbog pozitivnih biostimulativnih efekata, meki laser se koristi za lečenje brojnih bolnih stanja u usnoj duplji. Jedna od njih je herpes labialis. Cilj: Cilj ovog rada bio je ispitati efikasnost mekih lasera u terapiji herpes labialisa. Materijal i metod rada: U ispitivanju je učestvovalo 43 pacijenta. Kod 23 pacijenta primenjena je laseroterapija, a kod preostalih 20 standardna terapija Aciclovirom u obliku masti. Rezultati: Nivo statističke značajnosti razlika srednjih vrednosti bola između grupa bio je maksimalan (p<0,001). Pacijenti sa herpesnim lezijama imali su koristi od laseroterapije u smislu skraćenja progresije oboljenja, simptomi u vidu bola, peckanja, žarenja svedeni su na minimum. Ispitanici tretirani laserom imali su statistički značajno manju srednju vrednost bola u odnosu na ispitanike tretirane Aciclovirom (p<0,05). Zaključak: Na osnovu dobijenih rezultata može se zaključiti da se meki laser pokazao kao efikasna terapijska metoda u lečenju herpes labialisa, pa se preporučuje u tretmanima.


Introduction
Herpes labialis is a viral disease caused by Herpes simplex virus (HSV), which belongs to a group of DNA viruses.The natural host of HSV is a human who is a reservoir and carrier of the infection.The virus is transmitted by direct contact from person to person.The incubation period is 5-15 days.The incidence of HSV infection is high in over 90% of the population 1 .
After the first wave of the disease, which may be undetectable, or could manifest as tonsil-pharyngeal infection, HSV can persists in Ganglion trigeminale.Numerous factors could be a trigger, including fever, which accompanies some infectious diseases, sunscreen, mechanical injuries, menstrual cycle, psychological stress.Women are affected more than men, in ratio 2:1.The upper or lower lip are equally affected in 1-2% of the population 1,2 .
The disease begins by prodromal symptoms such as itching, burning or pain on the area where the herpetic lesions will develop.Within a few hours, erythema develops, followed by formation of vesicles.In a group, there can be 50 to 100 vesicles different in size.After a few days, vesicles burts, exudate comes out, and a yellowish crust is formed.After crustation, mild hyperpigmentation remains, which disappears over time.The next episode could recur on the same or some other site of mucosa.
For the treatment, local application of viral medicaments as well as soft laser could be used [3][4][5][6] .

The aim of the study
The aim of the study was to examine the efficacy of soft laser in the treatment of herpes labialis in comparison to traditional methods of treatment -acyclovir ointment.

Material and method
This study was carried out at the Faculty of Medicine University of Niš, Clinic of Dentistry, Department of Oral medicine and Periodontology.Out of 43 patients, 23 patients were diagnosed with Herpes labialis, which was treated by soft laser, and 20 patients were treated by standard, conventional therapy.U istraživanju je učestvovalo 23 ispitanika sa herpesom labialis, tretiranih niskoenergetskim laserom i 20 pacijenata kod kojih je korišćena standardna, konvencionalna terapija mašću Aciclovir (kontrolna grupa).
In the study, we used the GaAlAs soft laser-strenght 5mW, wavelenght 670nm, with a probe of 2mm in diameter, continuous regime, exposure time of 4 minutes.The pain was "measured" by the Visual Analogus Scale for pain, as well as clinical reduction of erythema and crustration.The basic statistical parameters (%, means, standard deviation and standard error) were used, as well as the t-test and χ 2 test.
The average age of these patients was 15,60±37,86 years, with a median of 34.00 years.
At the beginning of therapy, the study and control groups did not differ in the value of pain defined using the VAS scale.Pain decreased after the second therapy session in both groups, and at the time of the fifth session completely disappeared in both groups.It is evident that in the period from the third to the sixth session, the pain was significantly more pronounced in the control compared to the study group.
Significantly lower values of pain in the study group were recorded in the third (p<0.01) and forth (p <0.05) therapy sessions.

Discussion
Literature data relating to the application soft lasers in soft tissue diseases such as aphtae, herpes labialis, ulcus, etc. are extensive [5][6][7][8][9][10] .Herpes simplex virus 1 infection passes through several phases.Interesting results were obtained when the laser was used in the prodromal phase 11 .Then, laser therapy can cause suppression of infection and lesions cannot be seen 12 .Even when it is used in the later stages of infection, laser therapy provides a pain reduction, and accelerates the healing process 11,[13][14][15][16] .It is believed that during the vesicle phase, laser therapy can accelerate the virus proliferation 17 and cause an adverse effect on the process of healing of the lesion 18 .As the viruses rapidly proliferates at this stage, and laser increases the synthesis of ATP and nucleic acids in viruses, the use of laser is not recommended in this stage 19 .
On the other hand, one should bear in mind that the immune system is also under the influence of the laser 17,20 .Some authors suggest that immune cells against the HSV-1 virus are also proliferating, and they are active against a viral infection 21,22 .De Carvalho et al 21 used laser independently of the stage of the disease and the results showed the reduction of edema, and the size of the lesion.Vélez-González et al 25 applied laser after establishing the diagnosis and Rezultati ovog rada pokazuju dobar analgetski efekat mekih lasera, što je u saglasnosti sa rezultatima drugih autora 5,[7][8][9][10] .Naime, ispitanici tretirani laserom imali su statistički značajno manju srednju vrednost bola u odnosu na ispitanike tretirane Aciclovirom (p<0,05).
showed no side effects after radiation regardless of the stage of the disease.
The results of this study show good analgesic effect of soft laser which is in accordance with the results of other authors 5,[7][8][9][10] .In fact, the subjects treated with the laser had significantly lower mean value of the pain as compared to subjects treated with aciclovir (p<0,05).When it comes to preventive effects of laser treatment, it can be used during the latent phase when there are no signs of infection, and the interval between the appearance of a new herpetic attack extends 23,24 .Therefore, laser light is used in prodromal stage in order to reduce the extension of lesions, as well as in the latent phase in order to increase the interval between two recurrences.Laser can be used in the phase of crust to accelerate the healing.The major advantage of laser treatment is that it does not have negative side effects and drug interactions; it is particularly applicable in the elderly and immunocompromised individuals.

Conclusion
The subjects treated by soft laser had significantly lower mean value of the pain when compared to subjects treated with acyclovir (p<0,05).Based on the obtained results it can be concluded that the soft laser proved to be an effective therapy in the treatment of Herpes labialis, and therefore is recommended for its treatment.